5-Aryl-7-hydrazino-2-phenylpyrazolo[1,5-
c]pyrimidines
1 were used as precursors for the preparation of a new series of 5-aryl-8-phenylpyrazolo[1,5-
c]-1,2,4- triazolo[4,3-
a]pyrimidines
2. The reactions of
2 with certain electrophilic reagents gave the respective 6-substituted derivatives
3-
5 rather than the
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5-Aryl-7-hydrazino-2-phenylpyrazolo[1,5-
c]pyrimidines
1 were used as precursors for the preparation of a new series of 5-aryl-8-phenylpyrazolo[1,5-
c]-1,2,4- triazolo[4,3-
a]pyrimidines
2. The reactions of
2 with certain electrophilic reagents gave the respective 6-substituted derivatives
3-
5 rather than the 7-isomeric products. Formylation of the key compounds
1 with ethyl formate yielded the formyl derivatives
6. Furthermore, boiling of compounds
1 with acetic acid afforded 7-acetylhydrazino-5-aryl-2-phenylpyrazolo[1,5-
c]pyrimidines
7. Bromination of
7 yielded the dibromo- derivatives
8, while their iodination and nitration gave the monosubstituted derivatives
9 and
10, respectively. Also, treatment of
1 with boiling acetic anhydride yielded the triacetyl derivatives
11. The structure of synthesized products was confirmed by elemental analyses, IR,
1H NMR and MS spectra.
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